Note: Major spoilers for both Half-Life and Half-Life 2 are contained within.

HALF-LIFE
Deep beneath the earth of New Mexico lies a labyrinthine series of tunnels and chambers, the Black Mesa Research Facility, where secret teleportation experiments are being conducted. Taking part in the experiments is Gordon Freeman, doctor of theoretical physics, along with Dr. Isaac Kliener and Dr. Eli Vance, and under the administration of Dr. Wallace Breen. One experiment goes terribly awry, and a dimensional rift (also knows as a resonance cascade) allows terrifying, ravenous creatures to pour into the facility from the Xen borderworld.

Freeman is one of the few who manages to survive, and battles hostile aliens on his way through the facility. The U.S. Government dispatches heavily armed Marines and assassins to the complex, where they have orders to kill anything that moves… including humans. Freeman, now fighting both aliens and the army, makes his way to the Lambda Complex, where he learns that a powerful Xen creature is holding the portals open from the other side. Freeman enters Xen through a teleporter, destroying this creature, known as the Nihilanth.

The G-Man, a mysterious figure who has been shadowing Freeman during his perilous journey through Black Mesa, offers Freeman employment, with the alternative being abandonment in Xen with no hope of surviving. G-Man then places Freeman in stasis.

OPPOSING FORCE and BLUE SHIFT
(Half-Life Expansions) - Freeman isn't the only one battling his way through Black Mesa: A soldier named Adrian Shepard and a security guard named Barney Calhoun also have their own adventures. Shepard survives and is detained by the G-Man, while Calhoun makes it out of the complex to relative safety.

HALF-LIFE2
Welcome to City 17. Since the events of Half-Life, things have gone from bad to worse, and it appears that the planet Earth is under new management. The dimensional rifts that allowed horrifying creatures to spill into our world have widened, and portal storms have unleashed the deadly Xen creatures planet-wide. The surviving members of the human race have clustered into the cities for protection, but now find themselves facing and even greater threat: The Combine (pronounced COM-bine). Heavily armed and ruthless, the Combine, a powerful alien race who control their conquests through genetic modification and implantation, have taken over the planet and rule from a series of citadels, enormous black towers that slowly devour the cities they dominate. Draining the planet of its natural resources, turning humans into mind-controlled alien hybrid soldiers or ghoulish slaves, the Combine are driving the human race towards extinction. The liaison between the humans and Combine is none other than Dr. Wallace Breen, former administrator of the Black Mesa Complex. Xen creatures called Vortigaunts, once slaves forced to fight against humans in Black Mesa, have joined with the humans against the Combine.

Enter Gordon Freeman. The mysterious G-Man, for reasons known only to him, releases his prize "employee" into City 17. Once there, Freeman meets up with Barney, the former security guard from Black Mesa, Dr. Kliener, and Alyx Vance, Eli Vance's daughter. Due to a teleporter malfunction, Breen and the Combine detect Freeman's presence and Gordon is forced to flee City 17 through the city's canals and tunnels. Using a modified airboat provided by the rebel forces, he finds his way to a hidden base known as "Black Mesa East", where Dr. Eli Vance and Dr. Judith Mossman are working on teleportation technology to combat the Combine. Soon after Freeman's arrival, however, Combine forces invade and Freeman is forced to flee through Ravenholm, a town once filled with City 17 refugees but now crawling with nightmarish zombies, due to a Combine bombardment of headcrab-deploying rockets.

After Ravenholm's only survivor, Father Grigori, aids Freeman through the town, Gordon reaches Highway 17, a coastal road peppered with Combine roadblocks. Freeman learns that Eli Vance has been taken to Nova Prospekt, a prison-turned Combine facility, and heads there in a patchwork dune buggy to meet Alyx and rescue Eli. Along the way he'll have to combat not just enemy soldiers but also burrowing alien insects known as antlions. Once Freeman equips himself with theropods, he is able to tame the antlions and use them as weapons against the Combine.

As Freeman and Alyx return to City 17, they find their actions at Nova Prospekt have sparked a revolution. The remaining humans have picked up weapons and are fighting the Combine forces in the streets of City 17. The Combine are not backing down, however, employing gunships, suppression beams, and Striders, fifty-foot tall, three-legged mechanical monstrosities with devastating firepower. It's up to Freeman to battle his way through the city, employing citizens as squadmates, storm a museum that's being used as a Combine stronghold, defeat the Striders, and enter the Citadel for a confrontation with Dr. Breen. Along the way, Alyx is captured.

The only hope for the human race is for Freeman is to stop Dr. Breen and destroy the Citadel.

CONCERNEDThis comic strip is based on the ground-breaking PC game Half-Life 2, by Valve software, and is created with the brilliant Garry's Mod tool, which allows users to enter the game and basically play God by spawning and manipulating physical objects, posing character models, creating special effects, and taking pictures.

Those who have never played Half-Life 2 will be in the dark on a lot of the goings-on in the comic strip, as much of the dialogue and situations are pulled directly from the game or are based on the game's plot, history, and background. For those who someday plan to play Half-Life 2, read this comic with caution as there will be major spoilers.

Concerned is the story of Gordon Frohman, former Black Mesa entry-level employee, survivor of the Portal Storms and the Seven Hour War, and now earnest and hard-working citizen of City 17. Frohman is a simple guy trying to earn an honest buck in a post-apocalyptic world ruled mercilessly by hordes of heavily armed alien hybrid soldiers (called Combine) bent on draining the Earth of its last natural resource and exterminating the human race. He also enjoys playing backgammon.

Gordon Frohman arrives on the scene a few weeks before Doctor Gordon Freeman -- scientist, hero, anti-citizen, and star of Half-Life and Half-Life 2 -- first appears in City 17. Due to the similarity in their names, Frohman is often initially mistaken for the crowbar-wielding Freeman, though due to Frohman's chatty nature and general incompetence the error is usually sorted out fairly quickly.

While Gordon Freeman is brought to City 17 to free the remaining human population from the iron grip of the Combine, our mild-mannered Gordon Frohman has no such goals. In fact, he rather likes the Combine, thinks City 17 is a great town, and absolutely idolizes Dr. Wallace Breen, whose television show he watches religiously.

Frohman progresses through the world of Half-Life 2 in much the same way Freeman eventually does, though Frohman is motivated by different reasons. Frohman's adventures begin in the train station of City 17, just like Freeman's, and he soon meets Barney Calhoun, Alyx Vance, visits Dr. Kleiner's lab, makes his way through the canals, arrives at Black Mesa East, then travels through Ravenholm -- while apartment hunting -- up Highway 17, through Nova Prospekt, and then finally back to the City 17 he loves so dearly.

Naturally, Gordon Frohman doesn't command the respect and admiration that Gordon Freeman does, and thus is not given access to the weaponry and transportation that the rebels later provide their scientist cum action-hero with.

Below, we see the low-tech version of Freeman's airboat (called simply "a boat") as Frohman attempts to flag down a ride from a (perhaps unfriendly) Combine chopper.

Frohman also doesn't get to use Freeman's tau cannon-equipped buggy, though he can achieve a turbo boost on his bicycle when properly motivated.

All good things must come to an end, however, and one day, the much-anticipated Gordon Freeman shows up and threatens to turn Gordon Frohman's beloved City 17 into a battleground. The revolution begins and it's all-out war with the ultimate fate of the human race in the balance.